include/net/netlabel.h

   1 /*
   2  * NetLabel System
   3  *
   4  * The NetLabel system manages static and dynamic label mappings for network
   5  * protocols such as CIPSO and RIPSO.
   6  *
   7  * Author: Paul Moore <paul.moore@hp.com>
   8  *
   9  */
  10
  11 /*
  12  * (c) Copyright Hewlett-Packard Development Company, L.P., 2006
  13  *
  14  * This program is free software;  you can redistribute it and/or modify
  15  * it under the terms of the GNU General Public License as published by
  16  * the Free Software Foundation; either version 2 of the License, or
  17  * (at your option) any later version.
  18  *
  19  * This program is distributed in the hope that it will be useful,
  20  * but WITHOUT ANY WARRANTY;  without even the implied warranty of
  21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
  22  * the GNU General Public License for more details.
  23  *
  24  * You should have received a copy of the GNU General Public License
  25  * along with this program;  if not, write to the Free Software
  26  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  27  *
  28  */
  29
  30 #ifndef _NETLABEL_H
  31 #define _NETLABEL_H
  32
  33 #include <linux/types.h>
  34 #include <linux/net.h>
  35 #include <linux/skbuff.h>
  36 #include <net/netlink.h>
  37 #include <asm/atomic.h>
  38
  39 /*
  40  * NetLabel - A management interface for maintaining network packet label
  41  *            mapping tables for explicit packet labling protocols.
  42  *
  43  * Network protocols such as CIPSO and RIPSO require a label translation layer
  44  * to convert the label on the packet into something meaningful on the host
  45  * machine.  In the current Linux implementation these mapping tables live
  46  * inside the kernel; NetLabel provides a mechanism for user space applications
  47  * to manage these mapping tables.
  48  *
  49  * NetLabel makes use of the Generic NETLINK mechanism as a transport layer to
  50  * send messages between kernel and user space.  The general format of a
  51  * NetLabel message is shown below:
  52  *
  53  *  +-----------------+-------------------+--------- --- -- -
  54  *  | struct nlmsghdr | struct genlmsghdr | payload
  55  *  +-----------------+-------------------+--------- --- -- -
  56  *
  57  * The 'nlmsghdr' and 'genlmsghdr' structs should be dealt with like normal.
  58  * The payload is dependent on the subsystem specified in the
  59  * 'nlmsghdr->nlmsg_type' and should be defined below, supporting functions
  60  * should be defined in the corresponding net/netlabel/netlabel_<subsys>.h|c
  61  * file.  All of the fields in the NetLabel payload are NETLINK attributes, see
  62  * the include/net/netlink.h file for more information on NETLINK attributes.
  63  *
  64  */
  65
  66 /*
  67  * NetLabel NETLINK protocol
  68  */
  69
  70 #define NETLBL_PROTO_VERSION            1
  71
  72 /* NetLabel NETLINK types/families */
  73 #define NETLBL_NLTYPE_NONE              0
  74 #define NETLBL_NLTYPE_MGMT              1
  75 #define NETLBL_NLTYPE_MGMT_NAME         "NLBL_MGMT"
  76 #define NETLBL_NLTYPE_RIPSO             2
  77 #define NETLBL_NLTYPE_RIPSO_NAME        "NLBL_RIPSO"
  78 #define NETLBL_NLTYPE_CIPSOV4           3
  79 #define NETLBL_NLTYPE_CIPSOV4_NAME      "NLBL_CIPSOv4"
  80 #define NETLBL_NLTYPE_CIPSOV6           4
  81 #define NETLBL_NLTYPE_CIPSOV6_NAME      "NLBL_CIPSOv6"
  82 #define NETLBL_NLTYPE_UNLABELED         5
  83 #define NETLBL_NLTYPE_UNLABELED_NAME    "NLBL_UNLBL"
  84
  85 /*
  86  * NetLabel - Kernel API for accessing the network packet label mappings.
  87  *
  88  * The following functions are provided for use by other kernel modules,
  89  * specifically kernel LSM modules, to provide a consistent, transparent API
  90  * for dealing with explicit packet labeling protocols such as CIPSO and
  91  * RIPSO.  The functions defined here are implemented in the
  92  * net/netlabel/netlabel_kapi.c file.
  93  *
  94  */
  95
  96 /* NetLabel audit information */
  97 struct netlbl_audit {
  98         u32 secid;
  99         uid_t loginuid;
 100 };
 101
 102 /* Domain mapping definition struct */
 103 struct netlbl_dom_map;
 104
 105 /* Domain mapping operations */
 106 int netlbl_domhsh_remove(const char *domain, struct netlbl_audit *audit_info);
 107
 108 /* LSM security attributes */
 109 struct netlbl_lsm_cache {
 110         atomic_t refcount;
 111         void (*free) (const void *data);
 112         void *data;
 113 };
 114 #define NETLBL_SECATTR_NONE             0x00000000
 115 #define NETLBL_SECATTR_DOMAIN           0x00000001
 116 #define NETLBL_SECATTR_CACHE            0x00000002
 117 #define NETLBL_SECATTR_MLS_LVL          0x00000004
 118 #define NETLBL_SECATTR_MLS_CAT          0x00000008
 119 struct netlbl_lsm_secattr {
 120         u32 flags;
 121
 122         char *domain;
 123
 124         u32 mls_lvl;
 125         unsigned char *mls_cat;
 126         size_t mls_cat_len;
 127
 128         struct netlbl_lsm_cache *cache;
 129 };
 130
 131 /*
 132  * LSM security attribute operations
 133  */
 134
 135
 136 /**
 137  * netlbl_secattr_cache_alloc - Allocate and initialize a secattr cache
 138  * @flags: the memory allocation flags
 139  *
 140  * Description:
 141  * Allocate and initialize a netlbl_lsm_cache structure.  Returns a pointer
 142  * on success, NULL on failure.
 143  *
 144  */
 145 static inline struct netlbl_lsm_cache *netlbl_secattr_cache_alloc(gfp_t flags)
 146 {
 147         struct netlbl_lsm_cache *cache;
 148
 149         cache = kzalloc(sizeof(*cache), flags);
 150         if (cache)
 151                 atomic_set(&cache->refcount, 1);
 152         return cache;
 153 }
 154
 155 /**
 156  * netlbl_secattr_cache_free - Frees a netlbl_lsm_cache struct
 157  * @cache: the struct to free
 158  *
 159  * Description:
 160  * Frees @secattr including all of the internal buffers.
 161  *
 162  */
 163 static inline void netlbl_secattr_cache_free(struct netlbl_lsm_cache *cache)
 164 {
 165         if (!atomic_dec_and_test(&cache->refcount))
 166                 return;
 167
 168         if (cache->free)
 169                 cache->free(cache->data);
 170         kfree(cache);
 171 }
 172
 173 /**
 174  * netlbl_secattr_init - Initialize a netlbl_lsm_secattr struct
 175  * @secattr: the struct to initialize
 176  *
 177  * Description:
 178  * Initialize an already allocated netlbl_lsm_secattr struct.
 179  *
 180  */
 181 static inline void netlbl_secattr_init(struct netlbl_lsm_secattr *secattr)
 182 {
 183         secattr->flags = 0;
 184         secattr->domain = NULL;
 185         secattr->mls_cat = NULL;
 186         secattr->cache = NULL;
 187 }
 188
 189 /**
 190  * netlbl_secattr_destroy - Clears a netlbl_lsm_secattr struct
 191  * @secattr: the struct to clear
 192  *
 193  * Description:
 194  * Destroys the @secattr struct, including freeing all of the internal buffers.
 195  * The struct must be reset with a call to netlbl_secattr_init() before reuse.
 196  *
 197  */
 198 static inline void netlbl_secattr_destroy(struct netlbl_lsm_secattr *secattr)
 199 {
 200         if (secattr->cache)
 201                 netlbl_secattr_cache_free(secattr->cache);
 202         kfree(secattr->domain);
 203         kfree(secattr->mls_cat);
 204 }
 205
 206 /**
 207  * netlbl_secattr_alloc - Allocate and initialize a netlbl_lsm_secattr struct
 208  * @flags: the memory allocation flags
 209  *
 210  * Description:
 211  * Allocate and initialize a netlbl_lsm_secattr struct.  Returns a valid
 212  * pointer on success, or NULL on failure.
 213  *
 214  */
 215 static inline struct netlbl_lsm_secattr *netlbl_secattr_alloc(gfp_t flags)
 216 {
 217         return kzalloc(sizeof(struct netlbl_lsm_secattr), flags);
 218 }
 219
 220 /**
 221  * netlbl_secattr_free - Frees a netlbl_lsm_secattr struct
 222  * @secattr: the struct to free
 223  *
 224  * Description:
 225  * Frees @secattr including all of the internal buffers.
 226  *
 227  */
 228 static inline void netlbl_secattr_free(struct netlbl_lsm_secattr *secattr)
 229 {
 230         netlbl_secattr_destroy(secattr);
 231         kfree(secattr);
 232 }
 233
 234 /*
 235  * LSM protocol operations
 236  */
 237
 238 #ifdef CONFIG_NETLABEL
 239 int netlbl_socket_setattr(const struct socket *sock,
 240                           const struct netlbl_lsm_secattr *secattr);
 241 int netlbl_sock_getattr(struct sock *sk,
 242                         struct netlbl_lsm_secattr *secattr);
 243 int netlbl_socket_getattr(const struct socket *sock,
 244                           struct netlbl_lsm_secattr *secattr);
 245 int netlbl_skbuff_getattr(const struct sk_buff *skb,
 246                           struct netlbl_lsm_secattr *secattr);
 247 void netlbl_skbuff_err(struct sk_buff *skb, int error);
 248 #else
 249 static inline int netlbl_socket_setattr(const struct socket *sock,
 250                                      const struct netlbl_lsm_secattr *secattr)
 251 {
 252         return -ENOSYS;
 253 }
 254
 255 static inline int netlbl_sock_getattr(struct sock *sk,
 256                                       struct netlbl_lsm_secattr *secattr)
 257 {
 258         return -ENOSYS;
 259 }
 260
 261 static inline int netlbl_socket_getattr(const struct socket *sock,
 262                                         struct netlbl_lsm_secattr *secattr)
 263 {
 264         return -ENOSYS;
 265 }
 266
 267 static inline int netlbl_skbuff_getattr(const struct sk_buff *skb,
 268                                         struct netlbl_lsm_secattr *secattr)
 269 {
 270         return -ENOSYS;
 271 }
 272
 273 static inline void netlbl_skbuff_err(struct sk_buff *skb, int error)
 274 {
 275         return;
 276 }
 277 #endif /* CONFIG_NETLABEL */
 278
 279 /*
 280  * LSM label mapping cache operations
 281  */
 282
 283 #ifdef CONFIG_NETLABEL
 284 void netlbl_cache_invalidate(void);
 285 int netlbl_cache_add(const struct sk_buff *skb,
 286                      const struct netlbl_lsm_secattr *secattr);
 287 #else
 288 static inline void netlbl_cache_invalidate(void)
 289 {
 290         return;
 291 }
 292
 293 static inline int netlbl_cache_add(const struct sk_buff *skb,
 294                                    const struct netlbl_lsm_secattr *secattr)
 295 {
 296         return 0;
 297 }
 298 #endif /* CONFIG_NETLABEL */
 299
 300 #endif /* _NETLABEL_H */